AI · alternatives · 2026
24 alternatives to Custos — The bouncer for your AI agents
Stop AI agents from doing things they shouldn't.
Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Prices are shown for the 3 we have checked on their own sites, 3 of them free or with a free tier.
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Kastrafree tier, from $19.99/mo▲332Hi HN, Fernando and I built Kastra. Kastra intercepts AI agent tool calls and evaluates them against deterministic policies before they execute. We built this product to control pre- and post-inference workloads. This is aimed at developers using coding agents like Claude Code, Codex, Cursor, and OpenClaw. Kastra pushes an allow, hold, and deny decision before the action runs. You can build these policies in plain English from the web app. The interception engine evaluates the tools, targets, and parameters of every action at sub 1ms at a scale of billions of interceptions per day. We also…
Jul 2026 · kastra.ai · its alternatives →
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Venn.ai▲336Delegate real work to AI agents with safety guardrails
Mar 2026 · venn.ai · its alternatives →
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Copperhead – Hardware as Fast as Softwarefree tier, from $49/mo▲250An open-source AI agent that designs, documents and validates real PCBs from a prompt.
Sep 2026 · copperhead.sh · its alternatives →
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Custodian Labs is the fastest way for developers to ship AI agents with no infrastructure, no vendor lock-in, and privacy-safe by design.
Aug 2026 · custodianlabs.io · its alternatives →
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Open-source security gateway & static scanner for AI agents. Enforce role-based access control (RBAC), human-in-the-loop approvals, segregation of duties, and cryptographically signed, offline-verifiable audit logs. - makerchecker/MakerChecker
Jul 2026 · github.com · its alternatives →
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Hi HN! We just launched Codacy Guardrails, an IDE extension with a CLI for code analysis and MCP server that enforces security & quality rules on AI-generated code in real-time. It hooks into AI coding assistants (like VS Code Agent Mode, Cursor, Windsurf), silently scanning and fixing AI-suggested code that has vulnerabilities or violates your coding standards, while the code it’s being generated. We built this because coding agents can be a double-edged sword. They do boost productivity, but can easily introduce insecure or non-compliant code. One recent research team at NYU found that 40%…
2025 · its alternatives →
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Custosa▲15Permission and compliance layer for Enterprise AI
Mar 2026 · custosa.com · its alternatives →
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Your agent team, on your machine. Open-source harness for multi-user Claude agents. - yaodub/cast
Jun 2026 · github.com · its alternatives →
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We’ve been building visual rule engines (clear spreadsheet interfaces -> API endpoints that map incoming data to a large number of potential outcomes), and had the fun idea lately to see what happens when we use our decision table UI with Claude’s PreToolUse hook. The result is a surprisingly useful policy/gating layer– these tables let your team: - Write conditional, exception-friendly policies beyond globs/prefixes (e.g. allow rm -rf only in */node_modules/*, deny / or $HOME, ask if --force or network call; gate kubectl delete / SQL DROP with a clear reason) -…
Jan 2026 · github.com · its alternatives →
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At my last company, we connected Claude Code and Cursor to almost all our internal services via MCP. It made the team incredibly fast, but we hit a wall: permissions. If you give an agent "Read Only" access, it can’t actually fix anything. If you give it "Write" access, it’s only a matter of time before a hallucination or a bad prompt results in a deleted database or a nuked production bucket. We had a few "close calls" that convinced us that simply reducing IAM permissions makes agents useless. I built Armour (https://github.com/fuushyn/armour) to solve this. It’s a…
Jan 2026 · github.com · its alternatives →
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Runwallfree tier▲9A Runtime security layer that lets AI agents execute safely
Jul 2026 · runwall.vercel.app · its alternatives →
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Agentinel▲18Stop AI agents from installing malicious packages.
Jul 2026 · agentinel.habitwala.in · its alternatives →
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Stop AI agents from silently corrupting shared state
Jul 2026 · agent-coherence.dev · its alternatives →
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We just open-sourced Computer, a Computer-Use Interface (CUI) framework that enables AI agents to interact with isolated macOS and Linux sandboxes, with near-native performance on Apple Silicon. Computer provides a PyAutoGUI-compatible interface that can be plugged into any AI agent system (OpenAI Agents SDK , Langchain, CrewAI, AutoGen, etc.). Why Computer? As CUA AI agents become more capable, they need secure environments to operate in. Computer solves this with: • Isolation: Run agents in sandboxes completely separate from your host system. • Reliability: Create reproducible environments…
2025 · github.com · its alternatives →
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Project AI agents from unsafe actions before they execute.
Aug 2026 · agentfirewall.launchreadyal.com · its alternatives →
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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →